Question

What is the derivative of `(tanx)^-1`?

Answer 1

`-csc^2(x)`

Explanation:

We have:

`d/dx((tan(x))^-1)`

Using, `(tan(x))^-1=cot(x)`, we get

`d/dx(cot(x))`

`=-csc^2(x)`

Source:

http://www.math.com/tables/derivatives/more/trig.htm